SPDY protocol addresses the bottlenecks of HTTP protocols by one or more of the followings: (1) SPDY protocol minimizes the number of TCP connections through multiplexing requests; (2) SPDY protocol prioritizes requests where client devices could request some web resources to be delivered before others; (3) SPDY protocol compresses HTTP headers, and thereby improving the bandwidth utilization; and (4) SPDY protocol enables web servers to push web contents without a request from client device.
Note that, SPDY protocol requires that the web content be sent over a SSL/TLS connection with the TLS Next Protocol Negotiation (NPN) extension. Because SPDY requires the data transmitted to be encrypted, web content filtering cannot be performed without SPDY proxy support. As a result, malware, spyware, and/or virus subsequently can enter the network. Also, because web server can push contents without a request from the client device, the probability of a malware or spyware infecting the web content that enters the network is quite high.